Tongue Discoloration – for patients (Humans)

By David F. Murchison, DDS, MMS, Clinical Professor, Department of Biological Sciences;Clinical Professor, The University of Texas at Dallas;Texas A & M University Baylor College of Dentistry

The tongue’s papillae may become discolored if a person smokes or chews tobacco, eats certain foods or vitamins, or has colored bacteria growing on the tongue.

Black discoloration on the top of the tongue may occur if a person takes bismuth preparations for an upset stomach. Brushing the tongue with a toothbrush or scraping it with a tongue scraper can remove such discoloration.

pale and smooth tongue can be caused by iron deficiency anemia or by pernicious anemia, which is caused by a deficiency of vitamin B12.

strawberry-red tongue may be the first sign of scarlet fever or, in a young child, a sign of Kawasaki disease.

smooth red tongue and painful mouth may indicate general inflammation of the tongue (glossitis) or be caused by pellagra, a type of undernutrition caused by a deficiency of niacin (vitamin B3) in the diet.

Whitish patches on the tongue, similar to those sometimes found inside the cheeks, may accompany

  • Fever
  • Dehydration
  • The second stage of syphilis
  • Thrush (a fungal infection)
  • Lichen planus (an itchy skin disease that can also affect the mouth)
  • Leukoplakia (a flat white spot that develops as a result of prolonged irritation)
  • Mouth breathing

In geographic tongue, some areas of the tongue are white or yellow and rough, whereas others are red and smooth. The areas of discoloration often move around over a period of weeks to years. The condition is usually painless, and no treatment is needed. If people have symptoms, applying low doses of corticosteroids sometimes helps.


Merck Manual